ADSC 2010 Exam # 3 Study Guide Section 3 Lectures Diseases- Disease: an abnormal, pathological condition that affects parts or all of an organismo Acute disease: a sudden onset of clinical signs and short duration of illnesso Chronic disease: develop over a period of time and can be treated but notnecessarily cured- Etiology: the study of the cause of disease- Pathology: the study and diagnosis of a disease along with the tissues and organsassociated with it- Natural defense systemo Resistance (antibodies, acidic environment in stomach, etc.)o Immune systemo Behavioral adaptationso Genetics - Cause of diseaseso Parasiteso Bacterial infectionso Pathogens- Infectious diseases: diseases caused by living organisms- Four steps for vitality of infectious diseaseso Pathogen must enter its hosto Must adapt and multiply inside the host’s bodyo Exit the hosto Infect another host to start the cycle over again- Zoonotic disease: a disease that can be passed between animals and humanso 60% of infectious diseases in humanso Causes Contact with saliva, blood, urine, or feces of an infected animal Being bitten by a tick or mosquito (vector: inject DNA into cells) Eating or drinking something unsafe (unpasteurized milk, undercookedmeat, unwashed fruits and vegetables)o Examples: Malaria, E. Coli, West Nile, Anthrax- Epidemiology: the study of patterns, causes, and effects of health and diseaseconditions within a population- What defines a population?o Locationo Breedo Use- Epidemiologic Triado Agent Factors Virulence (strength of virus), Infectivity, Toxicity, Environmental hardinesso Host Factors How susceptible host is Intrinsic: can’t change (age, gender, genetics) Extrinsic: can change (previous exposure, reproductive status)o Environmental Factors Housing, Environmental Conditions, Nutrition- Iceberg Concept: observation in most cases that only a small amount of information isavailable because most of the data is hiddeno Clinical diseases: show observable symptoms that can be used to diagnose adiseaseo Subclinical diseases: no recognizable clinical symptoms due to disease being inearliest stages or so mild it is only diagnosed with special tests- How diseases are spreado Direct contacto Airborne organismso Introducing an animal carrying the subclinical disease into the herdo Contact with contaminated objectso Can be spread through vectorso Contaminated premises- Cattle Common Diseaseso Blackleg: highly fatal bacterial infection in young cattle Inflammation throughout body and fever Can be prevented by vaccines o Scours: diarrhea caused by bacteria, viruses, or parasites Occurs in younger cows Important to catch early due to dehydrationo Pink eye: contagious bacterial infection in eye  Starts with outer eye then goes to eyeball if not treated Can lead to blindness- Horse Common Diseaseso Cushings Syndrome: excessive secretion of cortisol due to pituitary gland tumor Weight loss, abnormal hair coat and ulcers Chronic; can’t be treatedo Strangles: very contagious bacterial infection affecting lymphoid tissue of upperrespiratory tract Can be prevented by vaccines Treated by lysing abscesses and with antibioticso Equine infectious anemia (EIA): regenerative disease similar to human AIDS Spread by biting insects Coggins test: required to prove your horse is tested negative within thelast year Weight loss, depression, & fever; results in euthanasia - Swine Common Diseaseso Glassers disease: caused by bacterium and affects younger pigs Fatigued; refuse to eato Porcine parvovirus: different from parvo in dogs Resistant to many disinfectants; contracted easily Deformed or mummified fetuses- Sheep Common Diseaseso Barber pole worm: internal parasite entering sheep by ingestion Weight loss, diarrhea, weakness, and can lead to death Deworming schedule to prevento Mastitis: bacterial infection of mammary gland Heavy milkers more prone Swelling and discolorationAnimal Health- Directional Terms on Animalo Cranial: towards heado Caudal: towards tailo Ventral: towards undersideo Dorsal: along the back- The Work-Upo History: medicines, originso Clinical examinations: TPRo Palpation: exterior, interioro Specimen collection: blood, urine, milk, feces)o Necropsy- Differential Diagnosis: given a symptom that could be associated with many diseases- Basic Vitals: will be given a number in one of the following categories and will be asked“is this in range?”Species Temperature Resting Heart Rate Respiratory RateCow 98-102.5 48-89 26-50Horse 99.1-100.8 28-40 10-14Goat 101.3-101.5 70-80 12-15Pig 101.6-103.6 70-120 32-58Sheep 100.9-103.8 70-80 16-34- Immune System Roleso Prevent entry of infectious agents Surface barriers: skin, mucous membranes, digestive and lung liningso Attack those that have gained entry- Innate Immunity: nonspecific immune responses that acts quickly but has a shortduration to buy body some time- Adaptive Immunity: more specific, vital form used to recognize cause of issue andsecrete specific things to fight; longer durationo Antibodies: proteins produced in body to attack infectious agents andneutralized them; produced in spleen and bone marrow Bind to antigen either to neutralize them or mark them for destruction byinnate immune systemo Passive Immunity: antibodies through placenta, colostrum or blood; handed o Active Immunity: body has to stimulate antibody production by either having thedisease and recovering from it or being vaccinated- Antigen: a toxin or foreign substance that induces an immune response- T Cell: produced in thymuso Can be cytotoxic (can kill without use of antibodies)o Helps B cells secrete antibodieso Memory of pathogen to increase effectiveness and speed next time - B Cell: produced in bone marrowo Produce antibodieso Memory of pathogen- Animal Criteria for Maintenanceo Acceptable Health: use nutrients properly; immune system capable of mountinga responseo Proper Nutrition: support immune system with enough energy to fuel immunecell production, enough protein for the structure of cells and antibodies, andenough vitamins & mineralso Under no-low stress: temperatures, weaning, handling, transportation Short-term stress: innate immune system- Closed Herd (extreme): doesn’t intake any animals- Open Herd: all in or all out for example-